phy: renesas: rcar-gen3-usb2: Add support for RZ/T2H SoC

phy: renesas: rcar-gen3-usb2: Add support for RZ/T2H SoC

Add initial support for the Renesas RZ/T2H SoC to the R-Car Gen3 USB2 PHY
driver. The RZ/T2H SoC requires configuration of additional
hardware-specific bits for proper VBUS level control and OTG operation.

Introduce the `vblvl_ctrl` flag in the SoC-specific driver data to enable
handling of VBUS level selection logic using `VBCTRL.VBLVL` bits. This is
required for managing the VBUS status detection and drive logic based on
SoC-specific needs.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250808215209.3692744-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>